Question: The arithmetic sequence $(a_i)$ is defined by the formula: $a_i = 10 + 5(i - 1)$ What is $a_{12}$, the twelfth term in the sequence?
From the given formula, we can see that the first term of the sequence is $10$ and the common difference is $5$ To find $a_{12}$ , we can simply substitute $i = 12$ into the given formula. Therefore, the twelfth term is equal to $a_{12} = 10 + 5 (12 - 1) = 65$.